There are many situations where it is desirable to have a highly portable flexible light transmitting device. Some examples of many uses of such devices are: dog collars; safety devices for backpacks, bicycles or clothing; wrist bands or bracelets; toys; and novelty devices including necklaces. While there have been many proposals for such devices in the past, such as shown in U.S. Pat. Nos. 5,046,456, 5,879,076, 6,193,385, and 7,140,327, they do not necessarily have absolutely the best light transmission for a given amount of battery power, nor do they have great adaptability, and they can be relatively expensive.
According to the present invention, a highly adaptable, relatively inexpensive, and efficient, portable flexible light transmitting device is provided. Because of its construction it can have many different lengths using the same light source, its light transmitting properties are excellent, and it can be made relatively inexpensively. The basic elements of the device of the invention that achieve these desirable results are a self-contained LED/battery component, a flexible light transmitting element positioned immediately adjacent but not embedding the LED(s), and an effective way to mount the self-contained LED/battery device and light transmitting element together in an operational relationship.
According to one aspect of the present invention, a light transmitting device is provided which comprises: A flexible elongated light transmitting element having first and second ends (and having a wide variety of cross-sectional configurations including, but not limited to, circular, elliptical and race-track). At least one LED (of virtually any color). At least one battery for powering the LED. And at least one positioning element which positions the LED so that it is immediately adjacent but not embedded in the first end of the light transmitting element so that light is efficiently transmitting from the LED along the light transmitting element. The term “immediately adjacent” in the specification and claims means that an LED is directly aligned with an end of the light transmitting element, is less than two centimeters away from it, and preferably essentially touches it.
The flexible elongated light transmitting element preferably comprises high clarity translucent or transparent thermoplastic polymeric material, such as thermoplastic polyurethane. Desirably the polymeric material is clear, however it can have a tint (e. g. red, blue or yellow) if desired.
The device further preferably comprises a printed circuit board including circuitry which operatively connects the LED to the battery, and an electrical switch in the circuitry which ultimately, through circuitry, connects or disconnects the LED to/from the battery. The printed circuit board mounts the LED, battery, and switch together in an integral module.
Desirably, the positioning element comprises a housing having first and second ends, the housing mounting the module therein and operatively connected at the first and second ends thereof to the first and second ends, respectively, of the light transmitting element (preferably through first and second end caps). The housing may be of hard plastic material, such as ABS, with the first and second housing end caps surrounding the light transmitting element adjacent the first and second ends, respectively, thereof, and operatively engaging the housing at the first and second ends, respectively, thereof. The end caps are preferably of flexible thermoplastic material such as silicone, thermoplastic rubber (TPR), or thermoplastic polyurethane (TPU).
Desirably, the housing has first and second openings formed therein between the first and second ends thereof, the first opening providing for ingress and egress of the module, and the second opening allowing access to the electrical switch for operation thereof. The openings may be covered with flexible material (e. g. TPR) covers.
Preferably the at least one LED comprises first and second LEDs, the first and second LEDs positioned immediately adjacent the first and second ends of the light transmitting element, respectively. In this case the printed circuit board includes circuitry which operatively connects the LEDs to the at least one battery, and an electrical switch in the circuitry which ultimately, through circuitry, connects or disconnects the LEDs to/from the at least one battery.
In one embodiment, the at least one battery comprises a plurality of button batteries mounted face-to-face and engaging at opposite ends thereof metal battery holders also mounted by the printed circuit board. The LEDs are on the opposite sides of the metal battery holders from the button batteries. In another embodiment, the at least one battery comprises a rechargeable battery, in which case the module further comprises a USB port mounted on the printed circuit board which allows recharging of the rechargeable battery.
Desirably, the circuitry includes an integrated circuit having a first terminal connected to the first LED through a resistor, a second terminal connected to the second LED through a resistor, a third terminal connected to the electrical switch, and two other terminals connected to voltage from the at least one battery and ground, respectively, and operatively connected together with a capacitor.
According to another aspect of the present invention a module is provided which comprises: At least one LED. At least one battery. A printed circuit board including circuitry which operatively connects the LED to the battery, and an electrical switch in the circuitry which ultimately, through circuitry, connects or disconnects the LED to/from the battery. The printed circuit board has first and second ends, and mounts the LED, battery, and switch together in an integral module with the LED at the first end thereof.
Preferably the at least one LED comprises first and second LEDs. The first and second LEDs are mounted on the printed circuit board at the first and second ends, respectively, thereof. The at least one battery may comprise a plurality of button batteries, or a rechargeable battery, as discussed above. The circuitry also is preferably as described above.
According to yet another aspect of the present invention there is provided a lighting unit which comprises: A housing of plastic material having first and second open ends. A module comprising first and second LEDs, at least one battery, and an electrical switch for operatively ultimately connecting, through circuitry, the battery to the LEDs. At least a first opening formed in the housing between the first and second open ends thereof, for allowing operative access to at least a part of the module within the housing. And wherein the module is mounted in the housing so that when the LEDs are on they shine light out the first and second open ends, respectively, of the housing.
It is the primary object of the present invention to provide a very adaptable, highly efficient, and relatively inexpensive light transmitting device. This and other objects of the invention will become clear from an inspection of the detailed description, and from the appended claims.